Thu, 17 Apr 2014 16:09:08 -0700
Added tag hs25.20-b11 for changeset b6a2ba7d3ea7
1 /*
2 * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 /*
26 * @test
27 * @bug 7190310
28 * @summary Inlining WeakReference.get(), and hoisting $referent may lead to non-terminating loops
29 * @run main/othervm/timeout=600 -Xbatch Test7190310
30 */
32 /*
33 * Note bug exhibits as infinite loop, timeout is helpful.
34 * It should normally finish pretty quickly, but on some especially slow machines
35 * it may not. The companion _unsafe test lacks a timeout, but that is okay.
36 */
38 import java.lang.ref.*;
40 public class Test7190310 {
41 private static Object str = new Object() {
42 public String toString() {
43 return "The Object";
44 }
46 protected void finalize() throws Throwable {
47 System.out.println("The Object is being finalized");
48 super.finalize();
49 }
50 };
51 private final static ReferenceQueue<Object> rq =
52 new ReferenceQueue<Object>();
53 private final static WeakReference<Object> wr =
54 new WeakReference<Object>(str, rq);
56 public static void main(String[] args)
57 throws InterruptedException {
58 Thread reader = new Thread() {
59 public void run() {
60 while (wr.get() != null) {
61 }
62 System.out.println("wr.get() returned null");
63 }
64 };
66 Thread queueReader = new Thread() {
67 public void run() {
68 try {
69 Reference<? extends Object> ref = rq.remove();
70 System.out.println(ref);
71 System.out.println("queueReader returned, ref==wr is "
72 + (ref == wr));
73 } catch (InterruptedException e) {
74 System.err.println("Sleep interrupted - exiting");
75 }
76 }
77 };
79 reader.start();
80 queueReader.start();
82 Thread.sleep(1000);
83 str = null;
84 System.gc();
85 }
86 }